.TH std::basic_streambuf::uflow 3 "2024.06.10" "http://cppreference.com" "C++ Standard Libary"
.SH NAME
std::basic_streambuf::uflow \- std::basic_streambuf::uflow

.SH Synopsis
   protected:
   virtual int_type uflow();

   Ensures that at least one character is available in the input area by updating the
   pointers to the input area (if needed). On success returns the value of that
   character and advances the value of the get pointer by one character. On failure
   returns traits::eof().

   The function may update gptr, egptr and eback pointers to define the location of
   newly loaded data (if any). On failure, the function ensures that either gptr() ==
   nullptr or gptr() == egptr.

   The base class version of the function calls underflow() and increments gptr().

.SH Parameters

   \fI(none)\fP

.SH Return value

   The value of the character that was pointed to by the get pointer before it was
   advanced by one, or traits::eof() otherwise.

   The base class version of the function returns the value returned by underflow().

.SH Note

   The public functions of std::streambuf call this function only if gptr() == nullptr
   or gptr() >= egptr().

   The custom streambuf classes that do not use the get area and do not set the get
   area pointers in basic_streambuf are required to override this function.

.SH Example

    This section is incomplete
    Reason: no example

.SH See also

   underflow reads characters from the associated input sequence to the get area
   \fB[virtual]\fP \fI(virtual protected member function)\fP
   overflow  writes characters to the associated output sequence from the put area
   \fB[virtual]\fP \fI(virtual protected member function)\fP

.SH Category:
     * Todo no example
